The invention provides an asphalt regenerant prepared from waste lubricating oil and a preparation method for the asphalt regenerant. The asphalt regenerant is prepared by using waste lubricating oil as a main raw material, and adding SEBS, petroleum resin, an anti-aging agent and a stabilizer into the waste lubricating oil, so that not only can aged asphalt components be restored to the state before aging, but also the modified effect on recycled asphalt can be realized; an elastic space net structure is formed inside the asphalt regenerant, so that the regenerability of the whole regenerant is greatly improved, and moreover, the regenerant is low in environmental pollution, and is environment-friendly; in addition, the preparation method is simple and lower in cost.